Abstract: Over the past decade, compliance checks of retail alcohol outlets have become a key enforcement strategy in efforts to reduce underage access to alcohol. Alcohol law enforcement agencies throughout the country use compliance checks to identify and sanction retail outlets that illegally sell alcoholic beverages to buyers under the age of 21. Compliance check programs are also used to monitor compliance rates in states and communities. Compliance rates, as measured by the results of compliance check programs, have improved considerably since these programs were first initiated. There is, however, concern by both researchers and law enforcement officials that the compliance check protocols utilized by alcoholic beverage enforcement agencies and police departments are becoming less effective, and published compliance rates based on compliance check programs may be unintentionally inflated. The reason for this concern is that the protocol most commonly used requires the underage operative to be truthful if asked about his or her age. This strategy is used to avoid potential legal challenges regarding entrapment. Over time, however, many sellers appear to have come to understand these protocols so well that they simply ask the underage operative their age. Because the operative is prohibited from lying about his/her age, the potential sale is prematurely interrupted at this early juncture - even before the need to ask for identification. A more realistic scenario would have the underage purchaser responding that he/she is of sufficient age and/or producing a false ID. In collaboration with the Vermont Liquor Control Board and the New Hampshire Liquor Commission, the proposed study will randomly assign either the standard protocol or one of two alternative and more realistic protocols to a sample of licensed on-premise and off-premise outlets in these two states. The observed rates of non- compliance will be compared across the three protocols for evidence of meaningful and statistically significant differences. Outlet characteristics and features of the purchase attempt that are related to non- compliance will also be identified. PUBLIC HEALTH RELEVANCE: Project Narrative: Compliance check programs are used by law enforcement agencies to identify licensed alcohol outlets that may be selling alcohol to underage persons. Concerns have been raised that the procedures used for these programs appear to be losing their effectiveness, and may also be overestimating actual compliance rates. The purpose of this study is to compare compliance check results from the standard procedure to those from two alternative protocols. Results from the study could lead to the use of more effective compliance check programs and produce more accurate estimates of compliance rates.